Inverters can convert electrical power of a power-generating unit from direct current into alternating current and feed it into a power supply system, for example an AC voltage supply system, and/or supply it directly to an electrical consumer in order to operate said consumer. In particular, generators which generate electrical power from regenerative sources, for example photovoltaic generators or wind generators, can be used as the power-generator unit here.
A housing of an inverter has to satisfy various requirements. These include, in particular, the provision of connections for direct current lines, alternating current lines and communication lines, the accommodation and cooling of power-electronics components such as switching elements and coiled wire products, as well as the shielding of the electronic components against environmental influences. Furthermore, an inverter is to be constructed in as compact as possible in terms of its external dimensions and its weight, wherein it is to be ensured that its components can be mounted satisfactorily. The specific embodiment of an inverter which satisfies the specified requirements should also be configured in a way which is optimum for costs.
Conventional inverters comprise a housing which is sealed off from the surroundings and has a heat sink at the rear, to which sink the heat-generating components which are arranged within the housing are thermally connected, such that the heat sink can absorb the waste heat from the components and output it to the external air. For example, EP2299582A1 discloses an inverter with a housing, wherein a cooling-air duct having cooling ribs which are oriented in the longitudinal direction of the cooling-air duct runs centrally over the rear side of the housing, and wherein power-electronics components in the housing rest on the inside of an external wall of the housing, which external wall forms a boundary face of the cooling-air duct.
EP455969A1 discloses a safety power supply having a closed housing with forcibly ventilated cooling devices which comprise a ventilation duct which runs in the housing and is separated therefrom in a sealed fashion, wherein the cooling devices comprise at least two heat-sink sections which are electrically isolated from one another and which define the ventilation duct, comprise cooling ribs which project into the ventilation duct and are designed for the separate attachment of heat-outputting components of a primary circuit and of a secondary circuit.
US20110261531A1 describes a switched-mode power supply with a housing in which a coolant duct, through which a coolant flows, runs through the housing, such that electronic components within the housing are cooled by the coolant.
DE102013022306A1 discloses an electric device with a housing, a heat sink and an air-directing part, wherein the air-directing part, the heat sink and the housing form a cooling-air duct, and a cooling-air stream is conducted through the cooling-air duct.
DE102013100607A1 discloses an inverter with a first housing module and a second housing module, in which a cooling-air duct which opens out into the surroundings of the inverter is partially bounded by the first housing module and partially by the second housing module in the circumferential direction.